'A number of the protesters arrested during the riots in recent weeks have been freed,' he said.

'Investigations are under way on the suicide of one of the protesters who died in prison,' said the official.

Some contradictory reports have been published by Iran's oppositions in exile on the fate of the protesters who were detained during the recent unrest in Iran which began in late December 2017 with sporadic protests against economic hardships and developed into violent riots due to provocations that were steered from outside Iran.